The Paul Scherrer Institute is a multi-disciplinary research institute which belongs to the Swiss Federal Institutes of Technology Domain covering also the ETH Zurich and the EPFL. It was established in 1988 by merging in 1960 established EIR and in 1968 established SIN . Currently, it is based in Villigen and Würenlingen.The PSI is a multi-disciplinary research centre for natural science and technology. In national and international collaboration with universities, other research institutes and industry, PSI is active in solid state physics, materials science, elementary particle physics, life science, nuclear and non-nuclear energy research, and energy-related ecology.It is the largest Swiss national research institute with about 1,400 members of staff, and is the only one of its kind in Switzerland.PSI is a User Laboratory and runs several particle accelerators. The 590MeV cyclotron, with its 72MeV companion pre-accelerator, is one of them. As of 2011, it delivers up to 2.2mA proton beam, which is the world record for such proton cyclotrons. It drives the spallation neutron source complex. The Swiss Light Source , built in 2001, is a synchrotron light source with a 2.4GeV electron storage ring. It is one of the world's best with respect to electron beam brilliance and stability. An X-ray free-electron laser called SwissFEL is currently under construction and is slated to begin operation in 2016.The proton accelerators are also used for the proton therapy program. Wikipedia.
Furrer A.,Paul Scherrer Institute |
Waldmann O.,Albert Ludwigs University of Freiburg
Reviews of Modern Physics | Year: 2013
Magnetic clusters, i.e., assemblies of a finite number (between two or three and several hundred) of interacting spin centers which are magnetically decoupled from their environment, can be found in many materials ranging from inorganic compounds and magnetic molecules to artificial metal structures formed on surfaces and metalloproteins. Their magnetic excitation spectra are determined by the nature of the spin centers and of the magnetic interactions, and the particular arrangement of the mutual interaction paths between the spin centers. Small clusters of up to four magnetic ions are ideal model systems in which to examine the fundamental magnetic interactions, which are usually dominated by Heisenberg exchange, but often complemented by anisotropic and/or higher-order interactions. In large magnetic clusters, which may potentially deal with a dozen or more spin centers, there is the possibility of novel many-body quantum states and quantum phenomena. In this review the necessary theoretical concepts and experimental techniques to study the magnetic cluster excitations and the resulting characteristic magnetic properties are introduced, followed by examples of small clusters, demonstrating the enormous amount of detailed physical information that can be retrieved. The current understanding of the excitations and their physical interpretation in the molecular nanomagnets which represent large magnetic clusters is then presented, with a section devoted to the subclass of single-molecule magnets, distinguished by displaying quantum tunneling of the magnetization. Finally, there is a summary of some quantum many-body states which evolve in magnetic insulators characterized by built-in or field-induced magnetic clusters. The review concludes by addressing future perspectives in the field of magnetic cluster excitations. © 2013 American Physical Society. Source
Paul Scherrer Institute | Date: 2014-04-25
A quantitative radiographic method uses X-ray imaging. The method uses a ratio of the absorption signal and the (small-angle) scattering signal (or vice-versa) of the object as a signature for the materials. The ratio image (dubbed R image) is independent from the thickness of the object in a wide sense, and therefore can be used to discriminate materials in a radiographic approach. This can be applied to imaging systems, which can record these two signals from the underlying object (for instance, an X-ray grating interferometer). Possible applications could be in material science, non-destructive testing and medical imaging. Specifically, the method can be used to estimate a volumetric breast density. The use of the R image and the corresponding algorithm are also presented hereafter.
ETH Zurich and Paul Scherrer Institute | Date: 2014-03-24
Paul Scherrer Institute | Date: 2013-12-06
An assembly of Hall sensors provides the following: the three averaged values for the magnetic field components are assigned to the same point in space, at the center of the Hall sensor assembly. This allows for the instantaneous measurement of the full field vector. With the appropriate electrical connections of the Hall elements from opposing surfaces of each pair, undesired planar Hall effect is practically cancelled out.
Paul Scherrer Institute | Date: 2014-03-24
A laser ablation cell (